1. Field of the Invention
The present invention relates to a system and a method of measuring fat content in a target organ and a recording medium of recording a fat content measuring program. More particularly, it relates to a system and a method of measuring a fat content in a target organ capable of measuring the fat content in the target organ by quantifying a representative gray level in the target organ from the gray level distribution of pixels in a ultrasonic section image in the target organ and a recording medium of recording a fat content measuring program.
2. Description of the Prior Art
The increase on fat content in a target organ of human body brings about various complications and the increase itself involves the dangerousness of functional disorder. For example, the fatty liver means the state that the liver cell in the human body unusually contains the excessive fat content, and does not cause a pain and has no subjective symptoms in itself. For a healthy person, the slight degree of the fatty liver can be brought about, but, in case where the degree of the fat is serious, it is frequently developed into complications or liver cirrhosis. Recently, since the modems are very concerned about food life and fatness, their interests are concentrated on the measurement of the degree of the organ fat content. Accordingly, the development of an inexpensive method of easily measuring the degree of the fat content in the organ has been required.
It is known that the fatty liver is closely related to the actual fat content in the hepatocyte, and, accordingly, various methods of measuring the quantified fat content have been suggested or used. Nevertheless, the development of the method of easily measuring the degree of the fat content of the organ at low prices has been successively required.
For example, computed tomography (CT) is used in obtaining the longitudinal section image of the organ in the human body. The CT has merits that the image resolution is high and the ratio of the fat to the other components can be accurately separated in the image, without being relatively affected from the photographing technique and the photographing condition, and, accordingly, the research for the CT has been actively processed. Nevertheless, the CT requires very high cost and has a problem in safety, because of radioactive exposure.
In addition, in order to measure the fat content in the organ, liver biopsy is performed. The liver biopsy uses a method of separating the organ, for example, liver tissue and analyzing the tissue and constituent thereof, and provides accurate result in all the liver disease diagnosis. Nevertheless, the procedure thereof is complicated and invasive. Also, in case where symptoms of the disease do not appear, it is difficult that it is applied to prevent the disease, because the liver biopsy is not performed.
The ultrasonic imaging method is widely used in the diagnosis of the organ by obtaining the longitudinal section image of the organ, for example, the image of an abdominal longitudinal section. Such ultrasonic imaging method is relatively cheap and simple. Also, the ultrasonic imaging method is safe and is not invasive because it does not use the radiation. Nevertheless, there are problems that the effect of the photographing condition and the photographing technique for the quality of the ultrasonic image is dominant and the reflection characteristics on the portion through which the ultrasound passes and the resolution thereof is not uniform. Therefore, when various kinds of diagnoses are performed through using a photographed image, the arbitrary analysis of the diagnostician is easily intervened. Accordingly, the reliability of the diagnosis is not perfectly obtained.
In case where the fatty liver index is clinically determined by using the image based on the ultrasonic imaging method, there are four levels composed of normal, mild, moderate, and severe levels. Even diagnosis specialists often determined the level inaccurately and an error probability reaches 20% at a maximum.
Therefore, the development of the method capable of providing the quantified fat content by using the simple cheap ultrasonic image which do not depend on the photographing condition is very required. The experiments for measuring the fat content by using only the ultrasonic image has been reported, but the basic problems of the ultrasonic imaging method are not solved. For example, it is difficult that the fat content is quantified and the reliability is secured, because of the distortions of the image characteristics and the gray level distribution due to the irregularity of the resolution.